A. Field of the Invention
The present invention pertains to a continuous water applicator or dampener for use with lithographic type printing presses and duplicators.
In the art of lithographic presses and similar types of reproduction equipment there has been an ongoing need for improvements in the dampening apparatus used to apply water to the plate cylinder. Although a wide variety of dampening devices have been developed for lithographic presses and the like there has been a particular need for improved apparatus which is powered by a separate drive motor wherein the speed of a metering roller and transfer roller may be selectively controlled with respect to a form or applicator roller drivably engaged with the plate cylinder itself.
The wide variety of multi-color printing carried out in lithographic or similar printing processes also requires relatively fine adjustment of the amount of water or dampening liquid applied to the plate cylinder and the uniformity of the application of water. Accordingly, there have also been problems with prior art dampening apparatus as regards the adjustment of the pressure between the respective rollers in contact with each other to control the amount of water transferred from the water fountain to the plate cylinder. In this regard there has been a need for improvements in the roller support structure whereby the positional relationship or engagement pressure between the rollers may be easily adjusted.
It is also particularly advantageous to provide means in a dampening apparatus for disengaging the metering and transfer rollers from the dampener form or applicator roller when operation of the dampening apparatus is not required and to be able to use the dampener form or applicator roller as an additional inking distribution roller. The present invention provides several improvements in the art of dampening apparatus for printing press and duplicating equipment which meet the desiderata discussed above as well as providing other features which are particularly useful and will be appreciated by those skilled in the art of such apparatus.